This application is based upon and claims the benefit of priority from the prior Japanese Patent Application No. 11-101138, filed Apr. 8, 1999, the entire contents of which are incorporated herein by reference.
The present invention relates to a battery check system for use in cameras. More specifically, the present invention relates to a battery check system for use in a camera which has a battery check feature for sensing the residual energy of a battery or batteries for operating the camera to detect whether the camera works properly or not and making a warning display through visual or audible means to prompt the user to replace the batteries.
The recent development of portable equipment is amazing under the circumstances that each piece of equipment that was used heretofore at the rate of one a family has come into personal use, and various battery techniques have been demanded accordingly.
Under such a background, although conventional primary personal computers and telephones were of stationary types, they have become battery-powered and even come into outdoor use for a long time.
In view of such trend of technology, importance has been increasingly attached to battery checking techniques that check batteries for residual energy. Various devices have been devised heretofore to conform to the characteristics of batteries.
In the field of cameras, a technique of detecting the battery voltage after the flash unit has been charged up is disclosed in Jpn. Pat. Appln. KOKAI Publication No. 6-265967.
This technique is characterized by controlling the second-time battery check operation in accordance with the supply voltage detected by the first-time battery check operation.
In U.S. Pat. 5,701,527 is disclosed a technique that provides against the so-called sleeping phenomenon which occurs when batteries are not used for a long time.
This technique aims at accurately checking batteries which exhibit high impedance at the initial discharge time as in the case of the sleeping phenomenon.
In the aforementioned prior art techniques, however, control is performed without taking into consideration the fact that batteries can be damaged, depending on battery conditions.
Particularly in the provision against the sleeping phenomenon, in relatively old batteries, unlike new ones, passing load current many times in the recovery wait state after discharge under heavy load will rather speed up the energy consumption of the batteries.
With the technique disclosed in the aforementioned Japanese Unexamined Patent Publication No. 6-265867, since the battery check after the flash unit has been charged up is performed on the basis of the result of the battery check prior to charging of the flash unit, the deterioration of the battery due to charging is not taken into consideration at all. In addition, no provision is made to prevent the sleeping phenomenon.
It is therefore an object of the present invention to provide a battery check system for use in a camera which achieves energy saving to allow users to take many shots with one-time battery replacement by performing control taking into consideration the sleeping phenomenon and the recovery characteristics of a battery used.
According an aspect of the present invention there is provided a battery check system for use in a camera comprising: a monitor circuit for detecting a condition of a battery used in the camera; and a control circuit for controlling the operation of the monitor circuit and controlling the operation of the camera according to an output from the monitor circuit, and wherein the control circuit causes the monitor circuit to detect changed conditions of the battery and determines a detection timing of the voltage of the battery based on a detection result of the monitor circuit.
According to another aspect of the present invention, there is provided a battery check method for detecting the voltage of a battery aboard equipment comprising the steps of: detecting a changed condition of the battery; and determining a detection timing of the voltage of the battery based on a detection result of the changed condition of the battery.
According to still another object of the present invention, there is provided a battery check system for use in a camera comprising: monitor means for detecting a condition of a battery used in the camera; and control means for controlling the operation of the monitor means and controlling the operation of the camera according to the output of the monitor means, and wherein the control means causes the monitor means to detect changed conditions of the battery and determines a detection timing of the voltage of the battery based on a detection result of the monitor means.
According to a further aspect of the present invention, there is provided a battery check system for use in a camera comprising: monitor means for detecting a condition of a battery used in the camera; and control means for switching the monitor means between a first mode in which a changed condition of the battery is detected and a second mode in which at least one of an operation of detecting and displaying the voltage of the battery at a predetermined time and an operation of enabling the camera to take a shot is performed, and wherein the control means switches the time at which the voltage of the battery is detected in the second mode according to the result of detection of the condition of the battery in the first mode.
According to another aspect of the present invention, there is provided a battery check system for use in a camera comprising: monitor means for detecting a condition of a battery used in the camera; charging means for charging an electronic flash unit for emitting an electronic flash of light; first detecting means for detecting at least one of a time after the termination of charging the electronic flash unit and a charging time; second detecting means for detecting the voltage of the battery and switching the operation of the camera on the basis of the detected battery voltage; and control means for switching the time at which the battery voltage is detected by the second detecting means according to a detection result detected by the first detecting means.
According to still another aspect of the present invention, there is provided a camera having a plurality of modes for determining a condition of a battery for operating the camera comprising: mode switching means for switching the modes; and control means responsive to the mode switching means for switching forms of display visible to users.
Additional objects and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. The objects and advantages of the invention may be realized and obtained by means of the instrumentalities and combinations particularly pointed out hereinafter.